<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>02_理解数据代理</title>
</head>
<body>
  <script>
    let obj = {x:100};
    let obj2 = {y:200};

    //简单的数据代理
    Object.defineProperty(obj2,'x',{
      get() {
        return obj.x;
      },
      set(value) {
        obj.x = value;
      }
    })
  </script>
</body>
</html>